Are Robots The Future Of Grapevine Pruning?

Are Robots The Future Of Grapevine Pruning?

In 2012, Purdue University received $6 million in grant funding to develop robotic pruning for grapes and apples. Now, developers are putting the finishing touches on a robotic pruner that could be available by next year, according to Purdue Associate Professor of Horticulture Peter Hirst.

While the project focused on both apple trees and grapevines, the work is farther along with grapevines, Hirst says.

Advertisement

Bret Wallach, president of Vision Robotics Corp., demonstrates the robotic pruner to grape growers. The pruner straddles the row and is blue. Blue does not occur in grapevines, so the visioning system can subtract the background from the grapevines.

“Grapevine is a more simplified canopy structure, so it’s quite easy to work with — it’s more of a two-dimensional structure, whereas apple trees are a three-dimensional structure,” he explains.

Purdue’s commercial partner for the project is a San Diego-based company called Vision Robotics Corp. Hirst says the company has created a prototype robotic harvesting machine that works well, but the focus now is on improving the speed and precision.

How It WorksThe machine has a series of cameras that take photos of dormant grapevines. It then builds a three-dimensional image of the vine based on the photos and applies various pruning rules. Based on those rules and the images, it decides where the pruning cuts should be made. It has two robotic arms, each one with a pruner on the end of it — one on each side of the vine. The machine makes the cuts and, when it’s done, moves forward 18 inches, taking pictures along the way before stopping to make the next series of cuts.

“Right now, the speed needs to be a bit quicker to make it cost effective, but I think we’re on track,” Hirst says. “The goal is that in about a year from now, they should have a machine that’s getting close to where humans are.”

But, of course, there are already benefits of a machine over human labor. The machine can work 24 hours a day, seven days a week, for example, and it doesn’t mind working in frigid temperatures. There’s also the issue of immigration and availability of labor.

The CostRight now, Hirst estimates the cost of the robotic pruner at about $150,000, and a lot of that cost is in the robotic arms.

“We’re looking at lower-cost arms, and that might be able to reduce the weight of the machine, which would be helpful,” he says.

Improving the speed is also a priority, which would decrease the cost per grapevine pruned.

“We’re seeing significant progress on that,” Hirst says. “I think within a year or so, we’ll be getting close to where we need to be.”